Why do we see the near side of the moon only??


by anonymoussome
Tags: moon
Wallace
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#19
Mar17-08, 05:49 PM
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Quote Quote by Holocene View Post
For the experts, is it safe to say that IF the sun lasted forever, all the material in the solar system would eventually be pulled into the Sun?
Not at all, there is no reason that the orbits of the planets should decay over time. Eventually you might expect that say the Earth might become tidally locked to the Sun (so that one side was always day and the other always night) but the radius of its orbit wouldn't change. Note that this is only true under the Sun lasting forever hypothetical. In reality the Red Giant phase of the Sun in several billions years time will come long before this and cause significant disruption to the inner solar system, but that is a different issue.
DaveC426913
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#20
Mar17-08, 08:54 PM
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Is this question satisfactorily answered for the OP?

Good.

Cuz the real answer is:

We only see the near side of the Moon for the same reason we only see the near side of the No. 3 Hook & Ladder Engine or the near side of the Pawtucket Light and Power building:

in order to see the far side, it would have to be completely transparent.
Ulysees
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#21
Mar21-08, 04:26 PM
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Tidal lock implies there would be no lock if the earth had no sea?

I reckon it is the bulges of the earth, both the equatorial one and the oceanic one (pointing to the moon at all times), that make it possible for a torque to appear. But then the moon has no equatorial bulge or ocean. So how can the moon experience a torque?
Ulysees
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#22
Mar21-08, 04:30 PM
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Quote Quote by Wallace View Post
Not at all, there is no reason that the orbits of the planets should decay over time.
In fact they should do the opposite. The sun has an equatorial bulge due to its rotation, therefore we should get something similar to the moon getting slowly further from the earth.
Ulysees
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#23
Mar21-08, 04:48 PM
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Quote Quote by Ulysees View Post
In fact they should do the opposite. The sun has an equatorial bulge due to its rotation, therefore we should get something similar to the moon getting slowly further from the earth.
Oopsa, I take it back, the bulge of the sun is aligned with the orbits of the planets and there is no equivalent to the tidal bulge of the earth-moon system.
russ_watters
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#24
Mar21-08, 05:22 PM
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Quote Quote by Ulysees View Post
Tidal lock implies there would be no lock if the earth had no sea?
No, the earth itself has a tidal bulge, like kneading some dough with your hands.
But then the moon has no equatorial bulge or ocean.
In fact, the moon does have a tidal bulge.

http://www.digipro.com/Trials/moon.html


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